what is Difference between structure and class in C++

[jinendrashankar]

Hi All,

Can any one have any idea about this issue

what is Difference between structure and class in C++
Other then by default structure have public scope and class have private scope For data member and member function .If there is no other difference between Class & structure then why we use 2 key world in C++ we can use either class or structure in C++ ?

[Meetee]

Hi All,

Can any one have any idea about this issue

what is Difference between structure and class in C++
Other then by default structure have public scope and class have private scope For data member and member function .If there is no other difference between Class & structure then why we use 2 key world in C++ we can use either class or structure in C++ ?

1) Strutures don't provide something like data hiding which is provided by the classes.

2) Structures contain only data while class bind both data and member functions.

3) Structure dosen't support the polymorphism, inheritance and initilization.

4) In a Structure we can't initilize the value to the variable but in class variable we can assign the values.

And you told is already one of the differences!

Regards

[gpraghuram]

1) Strutures don't provide something like data hiding which is provided by the classes.

2) Structures contain only data while class bind both data and member functions.

3) Structure dosen't support the polymorphism, inheritance and initilization.

4) In a Structure we can't initilize the value to the variable but in class variable we can assign the values.

And you told is already one of the differences!

Regards

Zodilla ,
I dont agree with what you have told.
Structures can have constructors, destructor, VTable, inheritance, overriding, overloading etc. everything a class can have.

Thanks
Raghuram

[Meetee]

Zodilla ,
I dont agree with what you have told.
Structures can have constructors, destructor, VTable, inheritance, overriding, overloading etc. everything a class can have.

Thanks
Raghuram

Raghuram,

I don't have ever encountered with such a structure!! Can u give an example to support this? It will clearify my doubt regarding this.

Okie.. I found examples of constructor and overloading! But couldn't found inheritance example!

Thanks

[scruggsy]

Raghuram,

I don't have ever encountered with such a structure!! Can u give an example to support this? It will clearify my doubt regarding this.

Okie.. I found examples of constructor and overloading! But couldn't found inheritance example!

Thanks

Try here.
Decent explanation of the only difference between structs and classes and the reason for having both keywords,

[oler1s]

Yup, no difference but the default access type. Yes, it is idiomatic to use structs for arbitrary data types, and classes for the whole, well, class thing. But C++ actually doesn't really differentiate between the two. Crazy, but true.

EDIT: You can express your disbelief as much as you want. If you find it so absurd, write some code and check it for yourself. C++ structs are not the same as C structs. Just because you use them idiomatically as C structs does not mean a thing.

[weaknessforcats]

Hey, just check it out for yourself.

Write a class with constructors, destructors and member funcitons. Once it's compiled an working go in there and change the class to struct and rec-compile. You will find that everything works as before.

Why is this??

Here's why:

1) The only way to group data variables together in C is to use a struct.
2) C++ is a replacement for C
3) The only way to group data variables together in C++ is to use a struct.
4) Object-oriented features (which you don't have to use) were added to C++
5) That involved a "class" with "public" and "private" members. This was due to the object-technology folks who use a "class of things" and an "instance of a class".
6) The class in C++ was implemented as a struct.
7) To make C++ look like an object-oriented lamguage, the "class" keyword was added as an alternate declaration of a struct.
7) The only difference is that the default access to a class is private whereas the default access for a struct is public.

[jac666]

(...)
7) The only difference is that the default access to a class is private whereas the default access for a struct is public.

C++ "class" = "struct" except:
1. The default access to the members of a class is private whereas the default access for a struct is public
2. The default inheritance is adequate to the default access.

struct A : B {}; // the same as: class A : public B {};
class A : B {}; // the same as: class A : private B {};

[weaknessforcats]

2. The default inheritance is adequate to the default access.

This is part of the default access: struct is public, class is private.

[gpraghuram]

Hey, just check it out for yourself.

Write a class with constructors, destructors and member funcitons. Once it's compiled an working go in there and change the class to struct and rec-compile. You will find that everything works as before.

Why is this??

Here's why:

1) The only way to group data variables together in C is to use a struct.
2) C++ is a replacement for C
3) The only way to group data variables together in C++ is to use a struct.
4) Object-oriented features (which you don't have to use) were added to C++
5) That involved a "class" with "public" and "private" members. This was due to the object-technology folks who use a "class of things" and an "instance of a class".
6) The class in C++ was implemented as a struct.
7) To make C++ look like an object-oriented lamguage, the "class" keyword was added as an alternate declaration of a struct.
7) The only difference is that the default access to a class is private whereas the default access for a struct is public.

Thanks for your explanation..
Raghuram